Touch screen devices have become increasingly popular as an input device for many reasons. Some reasons include an improved and more natural user experience, and the ability to eliminate external input devices thereby freeing up more room for a larger display.
Typical touch screen displays employ a touch sensor composed of multiple layers of conductive transparent material placed in front of a display device. Typically the conductive transparent layers of the touch sensor have metalized border areas that are used to make various electrical connections. These metalized border areas are often made from printed silver ink.
Manufacturers of devices employing touch screen technology often desire a large screen and a sleek cosmetic exterior. To accomplish this, they often employ touch screens that are as large, or nearly as large as the casing of the devices. Sometimes manufacturers even employ metal casings.
These metal layers in the touch sensors, along with any metal in the chassis poses a problem for many mobile device manufacturers. These mobile device manufacturers typically include a radio frequency (RF) transmitter and receiver which utilize an antenna to transmit and receive data and voice communications. In order to ensure clear transmission and reception from all sides of the device, manufacturers often cut-out a portion of the metalized borders, or metal chassis to allow for the RF antenna to radiate and prevent interference to its radiation performance from the metallic pieces.